NERVE-FIBRES AND NERVE-CELLS 123 



with the latter function a curious point arises. By a nerve- 

 cell, when physiologists and psychologists are assigning to 

 it its functions, is meant a large nerve-cell, such as occurs in 

 the anterior horn of the spinal cord or in the cortex of the 

 brain, striking objects from which it is difficult to divert 

 attention. They are so large and so wonderfully branching, 

 so picturesque, with their clean cut axis-cylinder-process, 

 which, after giving off collateral branches in the grey 

 matter, runs an unbroken course perhaps for a yard-length 

 in the trunk of a nerve, and its protoplasmic processes 

 ramifying like the limbs and boughs of an oak in winter, 

 frosted with innumerable spikelets known to anatomists as 

 "thorns." It is difficult to induce the members of a his- 

 tology class to withdraw their eyes from these attractive 

 structures or to pay attention to any others ; yet, for every 

 single large nerve-cell, there are scores of nerve-cells of 

 different orders, equally beautiful although extremely 

 minute. What work have they to do ? The most numerous 

 of them, the "granules," although they are exact repro- 

 ductions in miniature of the large nerve-cells, are sometimes 

 dismissed as "connective-tissue elements," even by 

 anatomists of the highest eminence, or as " abortive nerve- 

 cells." Yet the only reason we know why one cell is big 

 and another small is that the one is responsible for the 

 nutrition of a large fibre and the other of a little one. There 

 is no reason whatever for thinking that the big cell has the 

 right to modify the impulses which pass through it, still less 

 to originate impulses, while the little cell has no such 

 exalted prerogative. Indeed, we know that some of the 

 largest of nerve cells, the cells of the ganglia on the pos- 

 terior spinal roots, do not in any way modify the impulses 

 which pass through or by them. If physiologists inter- 

 preted the phenomena which they observe in their labora- 

 tories in the light of their own science, without any precon- 

 ceived notions as to what they ought to find, they would dis- 

 cover no evidence that nerve-cells possess any discriminating 



